. The descent of man, and selection in relation to sex. Evolution; Natural selection; Heredity; Human beings -- Origin. Chap. XII. Reptiles. 357. Chamceleon Owenii (fig. 36), from the West Coast of Africa, the male bears on his snout and forehead three curious horns, of which the female has not a trace. These horns consist of an excrescence of bone covered with a smooth sheath, forming part of the general integu- ments of the body, so that they are identical in struc- ture with those of a bull, goat, or other sheath - horned ru- minant. Although the three horns differ so much in appearance fro
. The descent of man, and selection in relation to sex. Evolution; Natural selection; Heredity; Human beings -- Origin. Chap. XII. Reptiles. 357. Chamceleon Owenii (fig. 36), from the West Coast of Africa, the male bears on his snout and forehead three curious horns, of which the female has not a trace. These horns consist of an excrescence of bone covered with a smooth sheath, forming part of the general integu- ments of the body, so that they are identical in struc- ture with those of a bull, goat, or other sheath - horned ru- minant. Although the three horns differ so much in appearance from the two great pro- longations of the skull in G. bifurcus, we can hardly doubt that they serve the same general pur- pose in the economy of these two ani- mals. The first con- jecture, which will occur to every one, is that they are used by the males for fighting together; and as these animals are very quarrelsome,69 this is probably a correct view. Mr. T. W. Wood also informs me that he once watched two individuals of 0. pumilus, fighting violently on the branch of a tree; they flung their heads about and tried to bite each other; they then rested for a time, and afterwards continued their battle. With many lizards, the sexes differ slightly in colour, the tints and stripes of the males being brighter and more distinctly defined, than in the females. This, for instance, is the case with the above Cophotis and with the Acnnthodactylus caper,sis of S. Africa. In a Cordylus of the latter country, the male is either much redder or greener than the Temale. In the Indian Calotcs nigrilabris there is a still greater difference; the lips also of the male are black, whilst those of the female are green. In our common little viviparous lizard (Zootocn vivipura) "the " under side of the body and base of the tail in the male are f bright orange, spotted with black; in the female these parts " are pale-greyish-green without ;70 We have seen that 69 Dr. Bucholz,
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